There are obstructions that force the water to flow out and around them. When kayaking a river, obstructions are your friends.
Obstructions, however, also provide rest opportunities. A sizeable obstruction, such as a boulder, will create a relatively calm piece of water behind it. Both have to do with obstructions, but a hole is not a place to rest. The way to tell the difference between a potential eddie and hole is to look for water going OVER the obstacle. Holes can be fun places to work on your skills. Holes are essentially churning, contrasting currents filled with air.
Obstructions, however, also provide rest opportunities. A sizeable obstruction, such as a boulder, will create a relatively calm piece of water behind it. Both have to do with obstructions, but a hole is not a place to rest. The way to tell the difference between a potential eddie and hole is to look for water going OVER the obstacle. Holes can be fun places to work on your skills. Holes are essentially churning, contrasting currents filled with air.